硅胶固定功能化离子液体的制备及其在HMF合成中的应用

通过氯丙基三甲氧基硅烷将磺基功能化离子液体--N-磺丙基咪唑盐化学键联到微球硅胶上，制得微球硅胶固定化离子液体（IL3）。用FTIR、TG、13C-NMR、SEM、BET及酸度测定等方法对IL3进行了表征，并考察其在果糖脱水合成5-羟甲基糠醛（HMF）过程中的催化性能。研究结果表明：氯丙基三甲氧基硅烷可以将磺基功能化咪唑型离子液体化学键联到微球硅胶上。微球硅胶固定化磺基咪唑离子液体能有效催化果糖脱水生成HMF。在45.4-IL3催化下、乙二醇甲醚(EGME)溶剂中、115℃反应5小时， HMF收率可达82.1％。使用后的催化剂可以方便地循环使用。但随次数增加，HMF收率明显下降。45.4-IL3催化剂循环使用四次后，HMF的收率下降为53.0%。

Immobilization of Functionalized Ionic Liquid on Silica and Its Application in Hydroxymethylfurfural Synthesis

the sulfonic group functionalized ionic liquid--1-H-3-(3-sulfonic acid)propylimidazolium chloride was immobilized on micro-ball silica-gel using 3-chloropropyltrimethoxysilane as coupling agent to obtain the silica-gel immobilized ionic liquid(IL3). The IL3 was characterized by SEM, FTIR, TG, 13C-NMR, BET, and titration its surface acidity. Its catalytic performance in the synthesis of 5-hydroxymethylfurfural (HMF) from fructose dehydration was investigated. The results indicate that 1-H-3-(3-sulfonic acid)propylimidazolium chloride could be immobilized on micro-ball silica-gel surface, and the IL3 was a good catalyst for the HMF synthesis from fructose dehydration. The yield of HMF is up to 82.1%, using 45.4-IL3 as the catalyst, with ethylene glycol monomethyl ether(EGME) as solvent at 115℃ over 5h. The used IL3 could be reused conveniently. But the yield of HMF dropped gradually with the more times of the IL3 recycled. After the IL3 reused four times, the yield of HMF decreased from 82.1% to 53.0%.